Is persisting antigen responsible for the chronicity of experimental allergic arthritis?

Animals were injected intra-articularly with antigen after prior immunization with that antigen in Freund's incomplete adjuvant in order to precipitate immune complexes in the surfaces of menisci, ligaments, and cartilage. On reimmunization with antigen in Freund's complete adjuvant 10 weeks later, generally an arthritis limited to the intercondylar fossa developed; but on intra-articular injection of antigen a second time a widespread arthritis developed in that joint. Thus immune deviation had not occurred and animals were in an immunological condition such as to be capable of developing widespread arthritis given the correct intra-articular stimulus. It is concluded that antigen, persisting as immune complexes, plays no part in maintaining widespread monarthritis, presumably owing to its inability to participate in a delayed hypersensitivity reaction as a result of sequestration.